The present invention relates generally to antenna mounting structures and, more particularly, to an improved base for mounting a mobile antenna on a support plate and for connecting the antenna to a coaxial cable.
A wide variety of antenna mounting structures have been developed for use with mobile radios and citizen band equipment. These structures find their greatest application in mounting mobile antennas to the sheet metal exteriors of automobiles, trucks, and other vehicles. Typical examples of prior art mounting structures are illustrated in U.S. Pat. Nos. 2,476,407; 2,513,116 and 3,123,665. While some of these prior art mounting devices have met with considerable commercial success, they all nevertheless suffer from a number of disadvantages which have limited their acceptance and use. For example, the structures heretofore proposed have a relatively complex construction requiring the use of a large number of parts. They are, therefore, not only expensive to manufacture, but they are also expensive to install since they require substantial installation time. In addition, the field reliability and performance of the prior art structures is less than satisfactory, due to their complex construction and the fact that they are frequently assembled and installed by individuals having little or no experience with the installation procedure.
Another problem commonly associated with prior art structures is the failure of the electrical connection between the outer conductor of the coaxial cable and the grounding plane. This failure occurs primarily in those prior art structures wherein the outer conductor of the cable is clamped between a stationary member and a cap which threadedly engages the base member. Therefore, as the cap is threaded onto the base member the fragile strands of the outer conductor are drawn and may easily break off entirely.